Tire-inflating mechanism



April 3, 1928.

w. e. CUMMINGP TIRE INFLATI NG MECHANI SM 2 Sheets-Sheet 1 Filed Nov. 28. 1924 INVENTUR. WILLIAM B-DRDDN ELIMM/NCT.

A ril 3, 1928.

w. G. CUMMING TIRE INFLATING MECHANISM Filed Nov. 28. 1924 2 Sheets-Sheet 2 a //vv-TuR. WILLIAM G'IJRDDN BuMMuvu.

ATTLIHNEY,

Patented Apr. 3, 1928.

UNITED STATES "PATENT orrics.

TIRE-INFLATING MECHANISM.

Application filed November 28,- 1924. Serial No. 752,749. r it i This invention relates to means for pumping automobile tires and more particularly to provide an automatic pump contained within the tire. I a x It has for its object to providea means for maintaining the air pressure in a tire operated by the pressure of the tire tread due to the weight of the vehicle.

It consists of a suction pump'within the tire which produces a vacuum when operated by the pressure of the tread of the tire and draws air into the pump, this air isforced out of the pump into the tire tube when the pressure is removed.

By the former art the pump compressed the air during the pressure of the tread and fed the compressed air into the tire tube, or drew air into the pump under normal pressure and forced it from the pump into the tire tube under the compression of the tread.

WVhereas in this device the air is sucked into the pump by the compression of the tread and is then forced into the tire when pressure being removed.

My invention is of simple and cheap construction and provides a reliable means of maintaining a suitable air pressure within a pneumatic tire. 7

Reference is made to the accompanying drawings in which Fig. 1 is a side view of the pump. 7

Fig. 2 is a central longitudinal cross'section on the line 2-2 of Fig. 1. 1

Fig. 3 is a vertical cross section on the line 33 of Fig. 2 without the toggles. I

Fig. 4 is a verticlecross section on the line 4- 1 of Fig. 2. I a

Fig. 5 is a top view ofthe rubber portion of the pump.

Fig- (Sis a horizontal cross section similar to that of Fig. 2, but showing the effect of compression and the expansion of the rubber resulting therefrom. V a

Fig. 7 is a side view of the toggle hearing plate. 7

Fig. 8 is a ing plate.

Fig. 9 is a perspective view of a toggle.

Fig. 19 shows the device in position.

bottom view of the upper bearthe pump resumes its normal shape on the Fig. 11 is an enlarged view of a form of inlet tube and air filter.

Fig. 12 shows the device in operation with the tire tread undereompression.

The pump consists of a rubber body portion 1, having slits v1O, radiating from its vertical axis. I

In the form shown the body portion is octagonal with upper and lower extending edges 11, and four triangular shaped slits radiating towards these edges.

The horizontal edges are cut away and wedge shaped cavities 12, formed between the upper and lower faces of the octagon.

' A series of toggles 00 channel shaped as shown in Fig. 9 are riveted over the edges 11, each pair being pivoted together by pins 81, which pass through the rubber edges 11. Suitable upper and lower bearing plates 1-, and 40, provide flanged bearings to which the toggles 3, are pivoted by pins 42.

The upper bearing plate supports cap or button 17, to which it is secured.

The lower plate 10, is centrally bored to receive the inlet tube 5. p This tube 5, is threaded and carries on its end the inlet tip 51, which is preferably made of semi-rigid material. A ball valve 52, controls the opening of the tip, 51.

An outlet tube 2, leads from the opening of the tip 51, of the inlet tube 5, and extends outwardly into one of the cavities 12.

A ball valve 21, in the tube 2, controls the outlet.

The inlet tube 5, is screwed into the stem tube 6. The latter tube 6, has an end flange 61, and is threaded outwardly. A locknut 62, rips the inner tube '80, of the tire.

The stem tube v6, passes through the rim 7, to which it is secured by a lock nut 63, and then enters the filter cap 9.

The filter cap 9, is composed of two parts, an outer cap 91, with perforations 92, and threaded to screw on the lower ring 93, of the inner cap 90, and an. inner cap 90, with a wire mesh or perforated wall 95, and a lower ring 93, adapted to screw on the stem tube 6. I

Over the inner cap wall 95, is a filter coat 96, of suitable material such as soft leather or other dust and moisture excludthe ing medium. A nut 97, and Washer 98, on the inlet tube 5, will seal the threading on the stem tube 6, from leakage.

When the tire 8, is fully inflated the but ton 17, of the pump'is some distance from the adjacent inner tube 80, as shown in Fig.

10, and the pump does not function.

' lVhere however the tire partially collapses as shown i11.l1ig. 12 the tread of the tire presses the button 17, upwards and operates the pump.

In Fig. 10 the lower plate 40,'is shown.

out of contact with the flange 61, of the stem 6. This is to show the adjustability of the pump. In actual operation this interval would be filled in bya nut to provide a substantial support for the inlet tube and Upon the pressure on the button being removedthe rubber body resumes itsnormal flated tire and form and the walls of the slits come together forcing the air out through the outlet tube 2, and valve 21, into the interior of themthereby increases the pressure therein. l

By means of adjusting the height of the button so that it will only contact with the inner surface of the tire when the air pressure therein is below the required normal pressure, the pump will only function when necessary to raise the air pressure. The tire pressure is thereby automatically maintained at therequired normal for eflic ent' service.

I urtherinore in the case of leaks of a slight nature or of slow effect the pump will function sufiiciently to meet a considerable loss and will avoid the necessity; of immediate repairs or change of tire.

The above detail form as described and shown in the drawings isonly given to disclose one method of carryingout my inven .tion and I do not in anyway l1m1t its scope to this form;

The broad principle of producing a vacuum within a tire by means of the depression of the tire tread, supplying air to fill the vacuum and 'i'orcingthat air out of the tom bearing plates, a resilient outlet valve from the pump into thetire, can becarried out by valved air inlet tube leading to the center of the rubber body, an air filter thereto beyond the rim and a valved outlet tube leading fromthe center of the rubber body to the inside of the tire. r l l 2. In a device of the class specified the combination of a Wheel rim and a pneumatic tire thereon," with a suction pump within thetire comprising a rubber body having slits radiating froman-axis radial to the Wheel, edges extendingoutwardly beyond the slits, channeled toggles riveted on the edges, journalled in pairs and pivoted to top and bottom bearing plates, a resilient button secured on the 'top plate,a valved air inlet tube leading through the rim and bottom plate to the center of the rubber body, and a valved outlet tube therefrom to the inside of the tire.

3. In a device of the class ispecified the combination of a Wheel rim and a pneumatic tire thereon, with a suction pump withinthe tire comprising a'rubber body having slits radiating from an axis radial to thewheel, edges extending outwardly beyond the slits,

channeled toggles secured on the edges, journalled in pairs and pivoted to to) and hotutt'on secured over the top plate, a valved #inlet tube leading throughthe rim and bottom plate to center of rubberbody, an air filter to the inlet tube,and a valved outlet tube from the center'of rubber body to the inside of the tire.

4. In a device of the class specified the combination of a wheel rimhand apneumatic tire thereon, with a suction pump'within the tire, meansto adjust the position of the pun'ip'within the tire, and an air inlet with inlet valve to the pump and an' outletwith pump to the interior ofthetire 5, In an automatic tire inflater the coinbination of a suction pump having valved inlet andoutlettubes with means to adjust the pump in. position within the tire.

WILLIAM eonlioon CUMMING. 

